Abstract
The emission line spectrum observed in jet-like Herbig-Haro objects could be excited by internal "crossing shocks" in a nonadiabatic jet flow. The authors explore this possibility by presenting predictions of Hα and [S II] images and position-velocity diagrams (i.e., spatially resolved line profiles) from nonadiabatic, steady jet models. They find that while these models do predict some of the observed characteristics of stellar jets, they fail to reproduce in detail the observational results. This suggests that other excitation mechanisms might also be important in stellar jets.
